Preliminary Study On Redox State Of HypoxicMouse Brain By Cryo-Imaging

That, the brain tissue redox metabolic continues well, is the premise to maintain normalbrain structure and function. It needs continuous and effective blood supply to keep thebalance of brain tissue metabolic redox status, because even a subtle change of blood flowor blood oxygen may lead to dramatic change of the metabolic redox status, which resultsin the concentration change of NADH and Fp in the brain cells’ mitochondria. In this thesis,we have combined the endogenous fluorescent molecular imaging techniques with thelow-temperature fixation technology of tissue energy metabolic status, and access to theinformation of the multi-sectional distribution of the whole Kunming mouse brainmetabolic redox status under hypoxia. The research would be helpful for raising awarenessof the relationship between the brain energy metabolism under different physiological andpathological conditions and the endogenous coenzyme, and supplying methods for thebrain metabolic abnormal specific diagnosis, treatment and following steps.This thesis includes:1. Three common fixation methods, decapitation freezing method, direct freezingmethod and funnel freezing method, were compared. At last, we decided to choose thefunnel freezing method according to the fixed complete degree of the sample structure andthe sample status homogeneity.2. According to the relationship between rate and temperature the of biochemicalreactions inside the body, we knew that to ensure a stable fixation metabolic state, we mustkeep them in liquid nitrogen. Therefore, this thesis explored the low temperaturemaintenance technology using self-designed corresponding modules to keep the sample inliquid nitrogen condition.3. We used the multi-channel three-dimensional fluorescence imaging system toacquire the mouse brain’s NADH and Fp coenzyme concentration distribution informationof death and different physiological conditions under the environment of low temperaturesin liquid nitrogen. Moreover, we found that the hypoxic mouse brain was in overall high oxygen reduction; and the regional difference between brain white matter and gray matterof the hypoxic and normal brains was just the opposite.